ALN169 &170 are a follow on from ALN144, again for TOTAL and destined for operations in W Africa. Although there are no significant differences in the vessels, lessons learnt from ALN144 have been encompassed into the new craft to optimise the design. They are durable, reliable workhorses, which will support line handling operations on the FPSO’s, undertake inspections of the FPSO hull and the CALM buoys. Although only fitted with a single propeller, to improve manoeuvrability, a bow thruster has been incorporated into the design. She is launched and recovered using a single point and Henrikson hook, for’ard of the bridge, which is married to a Palfinger davit.